Bispyribac-sodium (popularly marketed under names like "Nominee Gold") is one of the most widely used post-emergence herbicides for controlling barnyard grass (Echinochloa spp.) in direct-seeded and transplanted rice.
Step 1: Understanding the Concept:
Different crops have specific weed control requirements based on their growth conditions, planting methods, and sensitivity to herbicides. Step 2: Detailed Explanation:
Let us analyze the application of Bispyribac-sodium:
- Bispyribac-sodium is a post-emergence, broad-spectrum herbicide belonging to the pyrimidinyl carboxy family.
- It acts by inhibiting the enzyme acetolactate synthase (ALS), which halts the synthesis of branched-chain amino acids (valine, leucine, and isoleucine).
- It is widely used in rice (B) cultivation systems (including direct-seeded rice, transplanted rice, and nurseries) to control a wide range of grasses, sedges, and broadleaf weeds.
- Rice plants are highly tolerant to bispyribac-sodium because they can rapidly metabolize and detoxify the active molecule, whereas weeds like Echinochloa crus-galli (barnyard grass) are highly susceptible.
- It is not commonly used in maize, tomato, or okra due to potential phytotoxicity issues. Step 3: Final Answer:
The correct option is (B).
